Fan



April 22, 1958 PERRY 2,831,630

FAN

Filed Jan. 21, 1955 ATTORNEY INVENTOR. JOHN PERRY FAN John Perry, Kent, Ohio Application January 21, 1955, Serial No. 483,390 5 Claims. (Cl. 230134) This invention deals with a means of imparting a radial or axial velocity, or a combination of radial and axial velocities, to a fluid or fluids, liquid or gaseous, in particular air, by means of a rotary movement such as might be obtained from the shaft of an electric motor. Such devices are commonly called fans, blower wheels, impellors, etc., and will be called fans in what follows.

Up to the present time, fans to impart Velocities of fluids have been made in a variety of ways by means of stamping from flat metal, casting or molding, or a combination of such operations, and then assembling a number of parts so made into a complete fan. Sometimes such fans consist merely of a number of simple blades, suitably held together by attachment to a spider or other center piece; such fans are limited in the amount of fluid pressure they can produce because of the tendency for recirculation of fluid due to the pressure head created by the fan. Some fans are equipped with bafllcs (of which there are a variety of shapes) which tend to prevent such recirculation or pressure loss.

In a common type of fan, a number of blades are attached on one side to a circular piece of material, or are formed integral with the latter, while to the other side of the blades is attached a ring or shroud which confines the fluid to the space between the blades and thus opposes recirculation of the fluid, while the blades .are imparting a velocity to the fluid. Sometimes this ring or shroud is not attached to the fan itself but to an enclosure in which the fan is placed.

Thefan of the present invention is preferably formed in one piece although it might be made from several pieces. It can be formed conveniently from a single sheet of metal or plastic material or the like which is capable of being formed like metal; or it can be conveniently molded, cast, or otherwise made from metal or such material. It incorporates its own bathe as an integral part of it. This baflle, to a marked extent, opposes recircu lation of fluid and prevents escape of fluid in the inlet direction.

The fan may be produced in various sizes and can be used for the movement of fluids, gaseous or liquid, for the ventilation, cooling or heating of rotating systems such as an electric motor, for producing a fluid pressure such as in a pump or blower, and for producing a partial vacuum as in an exhaust fan or a vacuum cleaner. More generally, it may be employed where propeller fans, blower wheels, centrifugal fans, etc. are now used.

In one particular method of making the fan, a sheet of metal, usually flat, is cut (either lanced or slotted) in an annular area some distance from the fan center. The cuts lie in a generally radial direction so that each cut separates two adjacent fan blades. Each lance, or the edges of each slot, may be straight or curved or consist of a combination of straight and/or curved lines.

The outer edge of the fan of this invention is usually, but not necessarily circular, and is preferably continuous. Each blade is provided with a continuation which ex- 2,831,630 Patented Apr. 22, 19.58

tends to the circumference and forms a battle which prevents recirculation of the fluid without obstructing the flow of the fluid to or through the cuts between the blades. By thus reducing inlet and recirculation losses, the fan operates considerably more efliciently than conventional fans equipped with annular baflle rings.

Ordinarily, but not necessarily, the outer as well as the inner edges of the fan blades and baflles are joined. The portion of the fan connecting the inner edges of the blades may extend inwardly any distance and may extend to an opening at the center of the sheet by'means of which the fan is attached to a shaft or the like which rotates the fan, or the opening may be equipped with a hub or the like. nects the outer edges of the blades and bafiles may be flat and extend radially outward, or it may be cupped.

' The fan is located in a circular opening in a suitable housing, which together with the baflles formed integrally with the blades, prevents recirculation of the fluid at the fans circumference, making its operation highly efiicient.

According to the preferred method of forming the fan from a sheet of metal or the like, the blades are formed by bending the sheet between each two cuts to produce a wall which may be straight or angular and vertical, or it may be curved, in one or more directions, and it may be inclined toward or away from the fans center. Each such wall forms a blade which extends generally from the outer end of one cut on one side of it to the inner end of the adjacent cut on its opposite side. Extending outwardly from this wall or blade is the baflle. Thus, on one side of each cut, the blade is at or near the inner end of the cut and the baffle extends outwardly from it. On the other side of the cut, the 'blade is at or near the other edge of the cut and there is little or no baflle extending outwardly from it. The edge of the blade at the may have forwardly inclined blades or. 'backwar'dly in-I clined blades.

The invention will be further described in connection with the accompanying drawings, in which Fig. 1 is a plan view of one design of fan;

Fig. 2 is an edge view of the same;

Fig. 3 is a section on the line 33 of Fig. 1;

Fig. 4 is a view in perspective of this fan;

Fig. 5 is a plan view of a fan with a cupped edge;

Fig. 6 is an end view of the same; and

Fig. 7 is a section through the same on the line 7-7 of Fig. 5.

Both of the fans illustrated in the drawings are made from a flat sheet of metal by a single stamping operation. In referring to the various blades we shall use the numbers B1 to B8, although it is to be understood that there may be any number of blades and a corresponding number of cuts, baffles, etc. In this particular fan the cuts are slots, identified as S1, S2, etc. Each slot is bounded on one side by the inner edge of one blade and on the other side by the outer edge of an adjacent blade, the blades being identified as B1, B2, etc. We shall use the letter I to designate the inner edges of the blades, thus- I1, 12, etc. and the letter O to designate the outer edges, thus01, 02, etc. The baflles which extend outwardly from the blades are identified as L1, L2, etc. They are continuous in the drawing, but the cuts may extend to the circumference of the fan. There may be a hub in the central opening C of the fan, and the fan may be The portion of the sheetwhich con 3 mounted to a drive shaft or the like; or the central opening may be omitted and the fan attached to the driving member in some other manner.

The fan may be rotated'in either direction, that is, as a fan with backwardly or forwardly inclined blades.

The fan may be located in a circular opening in a housing that makes a relatively tight fit with the outer edge of the battles. There is little or no opportunity for the fan to recirculate air which has passed through it once. It may be located in a hole in a wall or in a conduit or other suitable location. The pressure developed by thefan is dependent upon the inclination of the blades and other factors, as in other fans.

In order to provide a better seal with a circular opening and to improve the strength and dimensional stability of the fan, the outer edge of the fan may be cupped downwardly to form a wall such as the wall 50 in Figs 5 to 7. This wall is shown as being substantially cylindrical but may slope downwardly or upwardly at any desired angle. The fan of Figs. 5 to 7 is identical with the fan of Figs. 1 to 4 except for this wall. This wall may in turn be turned outwardly or inwardly and be cut and bent to produce additional fan blades.

Although generally the slots will all be of the same size and shape, this is not necessary. For instance, longer slots may alternate with shorter slots. Thus, modifications of the illustrated design are contemplated within the scope of the invention.

What I claim is:

l. A fan formed with a central portion and a plurality of blades, openings in the fan surrounding said central portion, one of said blades extending between each two openings, each blade being at an angle to said central portion of the fan with the two ends of each blade at different distances from the center of the fan, the outer end of each blade being defined by one of the two openings and its inner end defined by the other of said two openings, and a bafile extending outwardly from each blade, said central portion lying essentially in one plane and the battles lying essentially in another plane, with the openings extending substantially from the one plane to the other.

2. A fan formed from a flat sheet with a central portion and a plurality of blades which are at an angle thereto, said central portion extending outwardly to the blades, one end of each blade being a greater distance from the axis of the fan than the other end, a series of cuts in the fan each defining an outer end and an inner end of adjacent blades, and a battle extending outwardly from each blade, said central portion lying essentially in one plane and the battles lying essentially in another plane parallel thereto, with the cuts extending substantially from one plane to the other.

3. The fan of claim 2 in which the central portion lies essentially in one plane and the battles lie essentially in another plane parallel thereto.

4. A fan with a central portion in one general plane, the central portion being surrounded by a battle which lies in a second general plane generally parallel thereto, blades connecting the two planes with one end of each blade nearer the center of the fan then the opposite end and with one side of each blade connected with said central portion and the other side connected with said bafile, and an opening between the inner end of each blade and the outer end of the adjacent blade which opening extends substantially from one of said planes to the other and is bounded on one side by the central portion of the fan and on another side by the bafile.

5. A fan with a central portion in one general plane,

blades surrounding the central portion, a bathe extend.

ing outwardly and all of the battles terminating in a generally cylindrical wall which is concentric with the fan and extends away from the central portion, said baflles lying in a second general plane generally parallel to the first, said blades connecting the two planes with one end of each blade nearer the center of the fan than the opposite end and with one side of each blade connected with the central portion and the other side connected with said bafiie, and an opening between the inner end of each blade and the outer end of the adjacent blade which opening extends substantially from one of said planes to the other and is bounded on one side by the central portion of the fan and on another side by the baffle.

References Cited in the file of this patent UNITED STATES PATENTS 693,328 Morgan Feb. 11, 1902 1,467,227 Capell Sept. 4, 1923 1,478,635 Cannon Dec. 25, 1923 1,669,569 Meyer May 15, 1928 1,872,483 Meyer Aug. 16, 1932 2,432,185 Watson Dec. 9, 1947 U. S. DEPARTMENT OF COMMERCE PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 2 83l,63O John Perry April 22, 1958 It is hereby certified that error appears .in the printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2 line 43, for "man" read fan sac column 4, line 14, for "then" read than u Signed and sealed this 3rd day of June 1958,

(SEAL) Attest:

KARL Ha AXLINE ROBERT C. WATSON Attesting Officer Comnissioner of Patents 

